Renal limited sarcoidosis presenting with acute kidney injury.

Sarcoidosis is a multisystem granulomatous disease of unknown etiology, characterized by noncaseating epithelioid granuloma, multinucleate giant cells, and tissue destruction. While lung and lymph node involvement is common, isolated renal involvement is rare. We report the case of a 55-year-old female patient, with renal limited sarcoidosis, who presented with worsening sensorium and acute kidney injury. The investigation showed elevated levels of serum calcium and angiotensinogen converting enzyme; the imaging study of the chest was normal. The kidney biopsy performed for nonresolving acute kidney injury showed noncaseating granulomatous interstitial nephritis and the presence of concurrent Immunoglobulin A (IgA)nephropathy. She responded to a therapy comprising fluid resuscitation, hemodialysis, and oral steroids.